Friction-clutch and the like.



' J. M. HEWITT & A. J. DRAKE.

FRICTION CLUTCH AND THE LIKE.

APPLICATION FILED our. 14, 1912.

1,077,831 P ten ed Nov. 4, 1913.

AME MI CHEL HEWITT, 0J5 MANQEESTE AND ARTHUR JAMES E, 0 HAL NGLAND," SSIGNQR 'lQ LUTCHg Q- LI'DmQF MA GHES EK EN L N rnrc'rroiv cnurcn 'AND rrrn KE.

To all whom it. mar/concern:

Be it known that we, JAMESMITGHELL HEWITT 'and ARTHUR; JAMES DRAKE, subj ects of the King. of Great Britain, and resi-r dents of Manchesterfin the *countyof -L3Il.--. caster, England, and .Hale, .inv thecounty of Chester, England; respectively, havetm-i vented new and useful Improvements in or- Applicable to Frictionfllutehes and the like, of which the followingisa specifications This invention .for improvements. .inaifrio, tion. clutches which areroperatedlby flexible bands, relates to the mechanism for expand-.- ing and contracting the bands.-- r w Toggle levers compressed by dnagii links or other suitable devices have beenrused-tQ tighten the bands on. the-: circumference :of the drum or pulley,.bycontractingeorshort= ening the suspended endsof the bands. These various; devicesefor. tightening the bands have hitherto given "trouble because of the centrifugal force acting :onitheloo'se toggles, drag linksor other .mechanis'm, and so either loosening oratightenirIg-th bands as the speed of revolution increased, thus making the action of the cl ltflll irregular varying speeds. The objects of this improvement. are:, To eliminate the centrifugal force by arranging the fulcrums of the band levers at the periphery of the clutch with length of levers toward the shaft center whereas formerly such fulcrums were located near one side with length of levers tangential to the circumference. To reduce the number of parts and simplify the construction of the clutch, by dispensing with toggles and exerting the clutching and declutching force direct on the levers. To avoid shock when the band is taking up its duty by placing the levers under the influence of springs which render the band elastic. To increase the clearance between the flexible band and the drum or pulley when out of gear by the flexible band being positively moved out of engagement by the levers through the solid eyes at each end of the band. To secure a permanent adjustment of the band by placing it under the influence of springs which take up the wear between the friction and clutch drum or pulley. To be able to regulate the exact horse power required from the clutch by so varying the tension of the p cificat o m rs w bandzspringsi and consequently the pressure ofitheband that ift-he requireddoad is exceeded, the clutch will slip To lessen the possibility of." oil escape by avoiding any holes extendingqfthrough the periphery in the: drum: or" pulley anddfulcruming the levers -insidelvthe latter.

. According totthis:inventionstwin. or sin-.

a- .convenient. :center for tightening them. on.

the drums. or "pul1eys, the said friction. bands embracingz the' latter irixopposite directions. Thebefore mentioneddeversmay be operatedaatitheir ends near'the centerz-of-the clutch by cone or wedge shaped longitudie nally movable plungersIcarried in a sliding yoke, these. plungers beingrso. constructed that when TthGiYOkEJlS moved backward or forward the i'levers moveiandthe bands are tightened or loosened on the drums or pullays-by means efsprings 1 1 pos ti e y. by the jconei or wedge shaped plungers. Single levers may be used with one end of the band fixed or adjustable by means of an adjusting screw on the body of the clutch, one or any number of bands may be used, as will be readily understood. without illustration. The said bands may be flexible or otherwise and form an almost complete circle or only a portion or portions thereof.

We attain these objects by the mechanism illustrated in the accompanying drawing, in which Figure 1 is a face view of the clutch with cover removed and Fig. 2 a sectional eleva tion.

Similar letters refer to similar throughout the various views.

Referring to the figures generally a is the shaft on which the clutch is mounted, b is the rim of the clutch body suspended from which at the points 0 are the operating levers d which carry the free ends of the flexible bands e which are tightened on the parts Patented Nov. 4. 1913.

App i a ion filed. ,q teheu 1912- eerieLNc- 517- drum or pulley f, secured to the shaft a by the wedge or cone shaped longitudinally movable plunger 91 which forces the levers.

(Z. apart.

We claim 1. In a friction clutch, in combination, a

tending toward the center of the'clutch, a

band encircling the said driving member and with ends pivoted to the said twin levers, a spring device on the said levers for forcing them together and thereby tighten the band around the said driving member and means for forcing the said twin levers apart and thereby releasing the said band.

2. In a friction clutch, in combination, a driving member located inside a driven member, twin levers fulcrumed to the said driven member near. its periphery and extending toward the center of the clutch, a band encircling the said driving member and with ends pivoted to the said twin levers, a spring device on the said levers for forcing them together and thereby tighten the band around the said driving member and means for forcing the said twin levers apart and thereby release the said band, the said spring device comprising a screw bolt passing through and springs thereon pressing against the said levers.

3. In a friction clutch, in combination, a driving member located 1ns1de a drlven member, twinlevers fulcrumed to the said driven member near its periphery and-ex-' 3 tending toward the center of the clutch, a band encircling the said driving member and with ends pivoted to the said twin levers, a

spring device on the said levers'for forcing them together and thereby tighten the band around-the said driving member and means for forcing the said twin levers apart and thereby release the said band, the said means comprising a plunger mounted longitudinally movable in the said driven part and adapted to enter between the free ends of the said twin levers to force them apart.

4. Ina" friction clutch, in combination, a driving member located inside a driven member, a plurality of twin levers fulcrumed at diametrically. opposite points to the said driven part near its periphery and longitudinally displaced in relation to each other, a plurality of bands located side by side-around the said driving part with ends pivoted. to the said levers respectively,

JAMES MITCHELL HEWITT, j ARTHUR JAMES DRAKE. Witnesses: i r

FERDINAND B. BOSSHARDT, i SrANLEv E. BR-AMALL.

Copies of this patent may be obtained for five cents each, by:addressing the Gommissioner of Patents,

Washington, I). C. i 

